Which of the following is NOT listed as a factor considered when selecting a dialyzer?

• A. Patient age
• B. Body size
• C. Membrane biocompatibility
• D. Brand ordered by MD

Answer: (A)

Selecting a dialyzer hinges on matching the patient’s physiologic needs with how the membrane will interact with blood. Body size influences the dialyzer’s surface area and clearance targets, so the goal is to achieve adequate toxin removal while avoiding excessive fluid removal. Membrane biocompatibility is crucial because some membrane materials can trigger inflammatory or allergic reactions; using a biocompatible membrane reduces these risks and improves tolerance during treatment. The physician’s brand order reflects the prescribed membrane type and compatibility with the treatment plan, ensuring the dialyzer fits the intended prescription. Patient age isn’t a standard criterion for dialyzer selection; while age can affect overall care, it doesn’t determine the technical fit or performance characteristics needed for effective dialysis.